H2S AND N2O PRODUCTION IN COASTAL SEDIMENTS AND THE REGULATION OF THEIR EMISSION INTO THE ATMOSPHERE

H2S AND N2O PRODUCTION IN COASTAL SEDIMENTS AND THE REGULATION OF THEIR EMISSION INTO THE ATMOSPHERE

Od 1982-09-01
do 1984-11-30

Dane projektu

Całkowity koszt:

Niedostępne

Wkład UE:

Niedostępne

Kraj koordynujący:

Denmark

Topic(s):

System finansowania:

CSC - Cost-sharing contracts

Cel

TO PROVIDE A BETTER INSIGHT

THE ATMOSPHERIC POLLUTION WITH SULFUR AND NITROGEN OXIDES FROM THE BURNING OF FOSSIL FUELS IS WELL ESTABLISHED. HOWEVER, THE DATA BASIS FOR REGULATORY POLICIES OF GASEOUS SULFUR AND NITROGEN EMISSIONS ARE SERIOUSLY LACKING INFORMATION ON NATURAL, BIOGENIC SOURCES. IN THE COASTAL ENVIRONMENT, THE MICROBIAL TRANSFORMATIONS OF SULFUR AND NITROGEN COMPOUNDS MAY LEAD TO SIGNIFICANT CONTRIBUTIONS OF E.G., H2S AND N2O TO THE ATMOSPHERIC BUDGET.

AN INTEGRATED FIELD STUDY OF H2S AND H2O EMISSIONS FROM COASTAL SEDIMENTS TO THE ATMOSPHERE IS PROPOSED TO BE CONDUCTED AT DIFFERENT LOCALITIES (LAGOONS, BAYS, FJORDS, ETC.) AT THE EAST COAST OF JUTLAND, DENMARK. THE EMITTED GASES WILL BE DIRECTLY COLLECTED. SEASONAL AND DIURNAL VARIATION OF THE H2S AND N2O EMISSION RATES WILL BE DETERMINED IN A VARIETY OF SEDIMENT TYPES, AS WILL THE GROSS PRODUCTION RATES OF THE GASES IN THE SEDIMENTS. THE BACTERIAL SULFATE AND NITRATE RESPIRATION WILL BE DETERMINED BY RADIOTRACER AND INHIBITOR TECHNIQUES.

IMPORTANT REGULATORY FACTORS SUCH AS O2, LIGHT AND BIOTURBATION IN THE SEDIMENT WILL BE EVALUATED IN LABORATORY EXPERIMENTS WHERE MICROELECTRODES FOR O2 AND H2S DETERMINATIONS WILL BE APPLIED FOR PRECISE CHARACTERISATIONS OF THE ENVIRONMENT AT THE VERY SURFACE OF THE SEDIMENT. ALSO THE DIRECT INTERACTIONS BETWEEN H2S AND N2O PRODUCTION WILL BE INVESTIGATED.

THE REACTION KINETICS OF CHEMICAL H2S OXIDATION IN THE OXIC ENVIRONMENT WILL BE STUDIED BY RADIOTRACER TECHNIQUES AND THE DIFFUSION OF THE GASES ACROSS THE STAGNANT BOUNDARY LAYER AT THE AIR-WATER INTERPHASE WILL BE INVESTIGATED USING MICROELECTRODES.

THE PROJECT WILL PROVIDE DATA ON THE EMISSION RATES OF H2S AND N2O IN A VARIETY OF COASTAL AREAS AND INSIGHT INTO THE REGULATORY MECHANISMS OF THE GASES PRODUCTION AND EMISSION TO THE ATMOSPHERE.